Up to now, as an ink-jet ink exhibiting good water resistance, there has been an ink which contains a water soluble dye dispersed or dissolved in a high boiling point solvent, and which contains a water soluble dye dissolved in a volatile solvent. However, a dye is inferior to a pigment in resistance characteristics such as light stability, and therefore ink using a pigment as a coloring agent has been required. But, it is difficult to disperse a pigment stably in an organic solvent, and it is also difficult to ensure stable dispersibility and ejectibility. On the other hand, in cases when ink using a high boiling solvent is applied onto a nonabsorbable base material, a solvent in the ink is not volatized, results in difficulty of drying via evaporation of the solvent. Accordingly, ink using high boiling solvent cannot be printed onto nonabsorbable base materials.
Generally, ink using a volatile organic solvent can be preferably printed onto a nonabsorbable base material due to adhesiveness of the used resin and volatilization of the solvent. However, since a volatile solvent is a major component, drying of the solvent by volatilization is almost instantaneous at the nozzle surface of the head, resulting in necessity of frequent maintenance. Resistance characteristics of the printing material to some solvents may not be sufficient because the ink essentially requires resolubility in a solvent.
Further, for an on-demand printer using a piezo element, usage of excessive volatile solvent increases frequency of maintenance, and also tends to induce problems such as dissolution and swelling of ink contacting materials in the printer. In addition, a volatile solvent has numerous restrictions as a dangerous material under the Fire Defense Law. Consequently, in an on-demand printer using a piezo element, it is desired to employ ink containing less volatile solvent.
What has recently attracted wide spread attention is active energy ray curable ink. Active energy ray curable ink solves the problem of volatility of a solvent, and further, can be used with solvent nonabsorbable base materials. However, components used for active energy ray curable ink usually exhibit relatively high viscosity. Therefore, it is difficult to design ink having good curability and high stability in the viscosity enabling ejection by conventional printers.
To overcome these problems, disclosed is an active energy ray curable composition containing an oxetane ring containing compound, an epoxy compound or a vinyl ether compound (refer to Patent Documents 1, 2 and 3).
However, as a result of study of the epoxy compounds described in the above documents, it was proven that curability and cured layer strength of the active energy ray curable composition are relatively good under low humidity conditions, but those under high humidity conditions are problematic, and additionally ejection stability at the nozzle, adhesiveness to base materials, resistance to solvents, and resistance to water are also problematic.
Patent Document 1 JP-A 2000-1482 (term of JP-A refers to as unexamined Japanese Patent Application Publication)
Patent Document 2 JP-A H8-143806
Patent Document 3 JP-A H7-53711